Steam-dome.



No. 852,735. PATENTED MAY 7. LQOV.

C. J. MELLIN. l

STEAM DOME.

APPLIOATION FILED 1250.5. nos.

WITNESSES CARL J. MELLIN, OF SCHENECTADY, NEW YORK.

STEAM-DOME.

Specification of Letters Patent.

Patented May 7, 1907.

Application led December 5, 1906. Serial No. 346.445`

To ffl/ZZ mfr/mit 'zit Tit/,Ly concern:

Be it known that I, CARL J. MELLIN, of Schenectady, ,in the county of Schenectady and State of New York, have invented a certain new and useful Improvement in Steam- Domes, of which improvement the following is a specification.

My invention relates to chambers or receptacles communicating with the upper portions or the steam spaces of steam boilers, and known as steam domes, from which steam is taken to be supplied to the cylinder or cylinders of an engine, and its object is to provide a steam dome which shall embody the advantages of strength, simplicity, and economy in construction, and which shall be particularly and desirably applicable in connection with boilers of comparatively large diameter and outside steam supply pipes.

The improvement claimed is hereinafter fully set forth.

ln the accompanying drawings; Figure l is a vertical longitudinal, central section through the upper and rear portion of a locomotive steam boiler, and through a steam dome illustrating` an embodiment of my invention; Fig. 2, a vertical transverse section throughthe steam dome g Fig. 3, a horizontal section through the same; and Fig. 4, a simi# lar section, illustrating structural detail.

In the practice of my invention, I provide a steam dome having a cylindrical body, 4l, which is an integral casting, of metal of proper character and strength, as, preferably, cast steel. The dome is cast with an open top, which is, in operation, closed by a suitable removable cap plate, secured in position by bolts or studs in the ordinary manner. The lower end of the body of the dome is entirely and permanently open, and the dome is secured to the top of the boiler, 4, above and around a steam supply opening, 4C, therein, through a flanged ring, 4l, which is riveted to the boiler and to the lower portion of the dome body, and a strengthening ring, 41h, is preferably fitted around the steam supply opening, on the inside of the boiler shell, and riveted thereto and to the flanged ring, 41a, as in present standard prac tice. Vhen so desired the flange ring may be cast integral with the dome, or it may be extended upward by interposing a cylin drical ring between it and the dome, to which the iiange and dome may be riveted independently. Ports, 41C, are formed on oppoa modification of' site sides of the body, 4l, each port being adapted to communicate with a lateral steam supply pipe (not shown) which is suitably connected to the dome, and the two ports, 4l, are connected by a circumferential channel way, 41d, the inner and. lower walls of which are cast integral with the body of the dome, which forms the outer wall of the channel way.

An inwardly projecting nozzle or passage, 41, is formed on the inner wall ol' the channel way, 41d, and a throttle valve chamber, 42, having a port, 42a, communicating with the nozzle, 41e, is secured thereto, the throttle valve chamber having an opening, controlled by a throttle valve, through which it communicates with the steam opening, 4e, and the steam space of the boiler. Communication between said steam space and the channel way, 41d, and its lateral steam supply pipe ports, 41C, is controlled by a throttle valve 43, which may bo of any suitable and preferred form, and in the instance shown, is of the balanced puppet type. The throttle valve, 43, closes on a seat, 42h, formed around a port or opening at the upper end of the chamber, 42, and is provided with a central steam passage way and a lower balancing piston, 43a, fitting truly in the chamber. Vertical movement is imparted to the throttle valve, to control and shut off, as desired, the flow of steam from the boiler into the throttle valve chamber, by a throttle lever, 44, pivoted to the rear end of the boiler and coupled by a rod, 44a, to a bell crank lever, 44h, pivoted to the boiler shell below the dome, the bell crank lever being, in turn, coupled by a link, 44, to one end of a lever, 44d, located above the throttle valve chainber. The opposite end of the lever, 44d, is coupled, by a link, 44e, to a lug on the throttle valve chamber, and the lever is coupled, intermediate of its ends, to the throttle valve. The specific construction of throttle valve and operating mechanism employed is not, however, an essential of my invention, and may be varied in the discretion of the constructor, without departure therefrom".

In the construction above described, the

channel way, 41d, extends entirely aroundA IOO scribed may be made, of ample strength for all requirements, at comparatively slight cost, and is specially advantageous in connection With boilers of large diameter used on locomotives having only a small amount of upper'clearance. rlhe lateral steam supply pipes may be readily connected to and disconnected from the dome, as may be required7 and the traverse orn steam thereto is as short and direct as practicable. The form of the dome is, further, such as to enable it to be readily and securely connected to the boiler. j

I claim as my invention and desire to secure by Letters Patent:

l. A dome for steam boilers comprising, in an integral casting, a cylindrical body having lateral steam supply pipe ports in its Wall, and a steam passage Way extending` circumferentially on the body from one of said ports to the other, and having a port for communication With a throttle valve chamber.

2. The combination of a dome having a cylindrical body With lateral steam supply pipe ports in its Wall, a throttle valve chamber located Within the domebody and compipe ports in its Wall and an integral steam y passage Way extending circumferentially on its Wall from one of said ports to the other, and a throttle valve chamber located Within the dome body and communicating by a lateral port with the steam passage Way.

4. The combination of a dome having a cylindrical body with lateral steam supply pipe ports in its Wall and an integral steam passage Way extending circumferentially on its Wall from one of said ports to the other, a throttle valve chamber located Within the dome body and communicating by a lateral port with the steam passage Way, and a throttle valve controlling an end port in said throttle valve chamber.

CARL J. MELLIN. 

